You might also look at the M.2 SSD. If this is starting to fail, this will cause the Nucleus to crash. If you connect a monitor to the Nucleus when you boot it, the BIOS may give you some indication of a hardware problem.
I had a problem with my Roon ROCK NUC which I initially built with a fairly cheap M.2 SSD. It was crashing once or twice a day. Sure enough, the BIOS was reporting problems.
When I replaced it with an Intel 660P M.2 drive, my NUC has been flawless. I have only had to reboot for software updates since then (last six months or so).
I had a problem with my Roon ROCK NUC which I initially built with a fairly cheap M.2 SSD. It was crashing once or twice a day. Sure enough, the BIOS was reporting problems.
When I replaced it with an Intel 660P M.2 drive, my NUC has been flawless. I have only had to reboot for software updates since then (last six months or so).